This invention relates to the recognition, characterization and representation of chemical notational indicia, including graphic and textual components thereof.
Computers have proven themselves useful as tools for manipulation and display of graphical information, as witnessed by the rapid transition to CAD from manual design systems and the widespread use of desktop publishing. These graphic capabilities are also important in the scientific research environment for modeling and displaying natural phenomena. In the chemical sciences field, graphical requirements are combined with another, the notion of a graphical database that can be searched and accessed on the basis of graphical characteristics.
Today, there are numerous databases comprising vast quantities of chemical and biological information which are dependent on graphic representations of molecules as the critical feature allowing for this data to be accessed graphically via substructure searching techniques. Once a database is created, it serves as the central facility for a wealth of other applications, such as information retrieval, publishing, scientific analysis, etc.
Facilities for entering graphical data are less advanced than those for manipulating it. For many years, this problem impeded the transfer to computers of paper systems, such as, utility maps, engineering diagrams, graphical chemical data, etc. To create a graphical object in digital format, an engineering diagram, for example, requires appreciable time on the part of a trained operator. Frequently, it requires a duplication of effort in the sense that the operator works from an already created printed drawing or hand sketch. Chemical structures that are candidates for addition to databases, for example, are often already printed in journals and catalogs, etc.